Occurrence Of Beetles Research Articles

Short Spatiotemporal Fire History Explains the Occurrence of Beetles Favoured by Fire.

The number and area of forest fires in northern Europe have been dramatically reduced during the past century, and several fire-favoured species are now threatened. To promote the recovery of these species, prescribed burning is often used as a conservation measure, and to optimise the use of these conservation burns, knowledge is needed on suitable fire frequency, size and placement in the landscape. The aim of this study was to analyse the effect of recent fire history (12 yrs) on beetles sampled using smoke attraction traps at 21 forest sites in a 10,000 km2 region. We analysed the odds of finding a fire-favoured beetle species or individual among the beetles in each trap using a new spatiotemporal connectivity measure and compared the results to non-fire-favoured and saproxylic species. For fire-favoured beetles, both the number of species and individuals significantly increased with connectivity to previous fires, while the other two groups did not. The spatiotemporal connectivity that best explained the patterns suggests that fire-favoured beetles mainly respond to fires within a 2 km range up to 2-3 years after the fire. Hence, to preserve fire-favoured insects, prescribed fires must be close in space and time to other fires-whether prescribed or natural.

To stay or not to stay? Temporal shifts in dung beetle occupancy in a cloud forest landscape

Abstract Dynamic occupancy model estimates the probabilities of occupancy, detection, extinction and colonization of individuals throughout seasons and is, thus, a useful tool for identifying whether individuals select a site to improve population phenology and fitness. We used multi‐season dynamics occupancy models to assess how abiotic factors (monthly variation, percentage of forest and edge and temperature) and biotic factors (female abundance) affect the demographic dynamics of coprophagous beetles Deltochilum mexicanum and Dichotomius satanas that differ in their habitat preferences in a human‐modified landscape in a cloud forest in Mexico. For both species, we captured a total of 1069 individuals with a density of 48.2 individuals per trap in forest areas and 14.8 individuals per trap in non‐forest areas. The species differed in their spatiotemporal occupancy dynamics in the landscape. Specifically, we found that monthly variation, percentage of forest cover and percentage of edge affected the models for both species. Each species showed a specific set of explanatory covariates for the model parameters, indicating that phenological and demographic regulatory mechanisms act as drivers of the spatiotemporal occupancy in a year period. We highlight the importance of considering abiotic factors (landscape characteristics) as drivers of occupancy, especially in highly heterogeneous landscapes. Such understanding is relevant to establish the effects of the landscape on the distribution and occurrence of dung beetles by determining how forest and generalist species differ in colonization and extinction patterns with respect to their phenology.

The First Report of GPS-based Mapping of Parthenium Beetle (Zygogramma bicolorata Pallister) Occurrence, Distribution and its Impact on Parthenium (<em>Parthenium hysterophorus</em> L.) in Northern Sri Lanka

Purpose: Parthenium hysterophorus L. is a globally recognized one of the most invasive noxious weeds. It has invaded more than 17 districts in Sri Lanka, and is listed under weed of national significance for eradication. Biological control using parthenium beetle Zygogramma bicolorata is one of the promising eco-friendly strategies for Parthenium management and is successful in many countries.Research Method: The biennial survey was conducted to explore the potential biocontrol agent Z. bicolarata of the parthenium and its dispersal around Northern Sri Lanka. Preliminary survey data identified sampling sites that were chosen to draw the distribution and density maps of Parthenium beetle (Z. bicolarata) using GPS tools. The field and greenhouse damage incidence of Z. bicolarata on Parthenium was calculated and subjected to ANOVA using SAS 9.1. Tukey's HSD multiple comparison test to identify the best treatment combination at P <0.05.Findings: The results exhibit that the Z. bicolarata distribution is confined to the Jaffna district in Northern Sri Lanka, and occurrence was first time in Valikamam North in the year 2019/20. The highest density of the Z. bicolorata population was 35-62 per m2 in the Valikamam North DS division in the years 2019/20 and 2020/21, respectively. The damage incidence varied from <10%-100%, but maximum field damage was 25->50% in Valikamam North whereas in the greenhouse 10 grubs inflicted 75-100% defoliation in 9±0.75 days.Originality/Value: This is the first report of occurrence of Z. bicolorata and detailed study of its distribution, damage on Parthenium to decide the biological Parthenium control programme.

A comprehensive synthesis of dung beetle records (Coleoptera, Scarabaeidae, Scarabaeinae) from Sabah, Malaysia.

Dung beetles play key roles in terrestrial ecosystems, contributing to many important ecosystem process and functions, such as nutrient recycling, parasite control and seed dispersal. Due to their tight associations with mammals and their responses to environmental change, they are also frequently used as environmental and biological indicators. Despite their importance, knowledge about dung beetles in Southeast Asia is limited. To address this information gap, we established a databasing project - "Mobilising data on ecologically important insects in Malaysia and Singapore" - funded by the Global Biodiversity Information Facility (GBIF). As part of this project, we compiled two extensive datasets - a sampling-event and occurrence dataset and a taxonomic checklist - for the dung beetles of Sabah, Bornean Malaysia. The sampling-event dataset documents 2,627 unique sampling events and 21,348 dung beetle occurrence records for Sabah. The taxonomic checklist includes 156 confirmed dung beetle species and 36 synonyms, totalling 192 records. These datasets have been made open access through the GBIF portal, which we hope will enhance the understanding of dung beetle taxonomy and their distributions in Southeast Asia. All data presented in this paper comprises of available information pertaining to the dung beetles of Sabah.

Taking advantage of opportunistically collected historical occurrence data to detect responses to climate change: The case of temperature and Iberian dung beetles.

This study introduces a novel approach to leverage high-resolution historical climate data and opportunistically collected historical species occurrence data for detecting adaptive responses to global change. We applied this procedure to the temperature data and the most comprehensive Iberian dataset of dung beetle occurrences as an illustrative example. To understand how populations of different species are responding, we devised a procedure that compares the temporal trend of spatial and temperature variables at the locations and times of all the occurrence data collection (overall trend) with the specific temporal trends among the occurrences of each species. The prevalence of various species responses is linked to life history or taxonomic characteristics, enabling the identification of key factors influencing the propensity to experience different effects from climate change. Our findings suggest that nearly half of the Iberian dung beetle species may be adversely affected by temperature increases, with a geographic shift being the most common response. The results generated through the proposed methodology should be regarded as preliminary information, serving to formulate hypotheses about the diverse responses of species to climate change and aiding in the selection of candidate species capable of coping with challenges posed by changing temperatures.

Výskyt a význam kůrovců rodu Pityokteines v porostech jedle bělokoré (Abies alba)

Silver fir (Abies alba, Mill.) is threatened by many factors in Central Europe, among which bark beetles of the genus Pityokteines play an important role. To improve the silver fir conservation, it is essential to adopt appropriate management practices. For this reason, we studied the occurrence of Pityokteines bark beetles in four sites located in climatically different conditions. In each site, five WitaTrap 5-segment pheromone funnel traps were placed from early April to late September in both 2021 and 2022. Two species, P. spinidens and P. vorontzowi, were captured. P. vorontzowi was significantly more abundant at all sites. Individuals of both species were recorded in the traps mainly in the period of April–August. The most abundant occurrence of beetles was at the site Nižbor, which can be explained by regional climatic differences (lowest elevation, higher mean temperatures and lower mean precipitation). The differences between sites can be also explained by different methods of forest protection applied. The study confirmed the presence of Pityokteines bark beetles and their dependence on climatic characteristics and forest management.

Širenje, masovna pojava i prve štete od vrste Ophraella communa LeSage, 1986 na vrsti Ambrosia artemisiifolia L. u kontinentalnoj Hrvatskoj

Based on targeted faunistic surveys, 34 new occurrences of ragweed leaf beetles (Ophraella communa, LeSage) in ten counties of continental Croatia are presented. From mid-July to the end of September 2022, the 34 locations, where ragweed (Ambrosia artemisiifolia L.) regularly occurs, were visually inspected. All developmental stages of the insect were found at all locations during July and August, while only adults were found at all locations in September. At 12 locations, ragweed infestation was estimated to be less than 10%. At 10 locations, damage caused by feeding ranged from 10 to 50%, and at seven locations from 50 to 80%. The mass occurrence of ragweed leaf beetles and complete destruction of common ragweed plants in Croatia was recorded at five monitored locations in four counties. A high level of foliar damage indicates that the species has been well established in the monitored area. The ragweed leaf beetle appears to be spreading rapidly over large areas and is capable of effectively controlling invasive common ragweed. Future work should focus on monitoring the spread, establishment, and impact of this species in Croatia and its inclusion in biological ragweed control measures.

American Burying Beetle (Coleoptera: Silphidae) Occurrence at Reservoir Shoreline and Hand-Planted Forest at the Western Limit of Their Range

The largest North American Silphidae, the American burying beetle (ABB), Nicrophorus americanus Olivier, has been extirpated from ∼90% of its historic range and is federally threatened. Two distinct populations in the Southern (Oklahoma and Arkansas) and North-Central United States (Nebraska and South Dakota) persist at the western edge of the ABB's former range. In Nebraska, the western limits of occurrence are associated with Merritt Reservoir and linked irrigation canals. ABBs are also found at the nearby hand-planted McKelvie National Forest. While habitat alteration and fragmentation are likely the primary reasons for ABB decline, few studies have examined their response to human habitat modifications unrelated to urbanization or agricultural conversion. Through five-day sampling periods with carrion-baited pitfall traps, ABB were captured and recorded in June and August from 2015 to 2017 at Merritt Reservoir and McKelvie National Forest in Cherry County, Nebraska. Traps were placed in transects (N = 4) at each location with reservoir traps set at the shoreline, transition, and upland habitats and forest traps set in the prairie, transition zone, and pine forest. At Merritt Reservoir, 651 ABB were captured, with significantly more collected at the shoreline. Concurrently, 23 ABB were captured at McKelvie Forest, with more ABB found within the forest compared to nearby prairie. These findings support previous suggestions that the western distribution of ABB is limited by moisture. Further investigation may indicate that reliable soil moisture associated with altered habitats in Nebraska could support ABB and potentially allow western range expansion.

The Spread of the Japanese Beetle in a European Human-Dominated Landscape: High Anthropization Favors Colonization of Popillia japonica

The impact of invasive species is not limited to the loss of biodiversity; it also represents significant threats to agriculture on a global scale. The Japanese beetle Popillia japonica (native to Japan but an invasive agricultural pest in North America) recently occurred in the Po plain (Italy), one of the most cultivated areas in southern Europe. Thus, our aims were to identify (i) the main landscape predictors related to the occurrence of the Japanese beetle and (ii) the areas of potential invasion of the Japanese beetle in the two Northern Italian regions in which this invasive species currently occurs, Piedmont and Lombardy. Specifically, we combined Japanese beetle occurrences available in the citizen science online platform iNaturalist with high-resolution landscape predictors in an ensemble approach and averaged the results of Bayesian generalized linear and additive models developed with the integrated nested Laplace approximation (with stochastic partial differential equation). We found that the occurrence of the Japanese beetle was negatively related to the percentage of broadleaf forests and pastures, while it was positively related to sparse and dense human settlements as well as intensive crops. Moreover, the occurrence of the Japanese beetle increased in relation to the percentage of rice fields until a peak at around 50%. The Japanese beetle was likely to occur in 32.49% of our study area, corresponding to 16,000.02 km2, mainly located in the Po plain, low hills, and mountain valleys. We stress that the Japanese beetle is a high-risk invasive species in human-dominated landscapes. Thus, we strongly recommend that local administrations quickly enact pest management in order to reduce further spread.

Papules, pustules, and rhinoconjunctivitis in a 4-year-old

Papules, pustules, and rhinoconjunctivitis in a 4-year-old

Relationships between the fecundity of bark beetles and the presence of antagonists

Although previous research has documented the occurrence of antagonists of bark beetles, the studies have only evaluated individual antagonists and have not assessed the overall effect of all antagonists on adult beetles. In this study, we determined which body-cavity antagonists were associated with a reduction in the fecundity and maternal gallery lengths of two important species of bark beetles: Ips typographus on Norway spruce and I. cembrae on European larch. We evaluated these relationships under natural conditions by collecting maternal females in galleries and examining their internal organs. The antagonists in the I. typographus hemolymph had significant negative associations with fecundity and gallery length. These antagonists were mainly nematodes and parasitoids in the hemocoel. In contrast, a positive association between gregarine presence and I. typographus fecundity was found. No antagonist that was likely to significantly alter I. cembrae fecundity or maternal gallery length was proven. Our study provides the first comprehensive assessment of antagonists that may have the potential impact on reduction the fecundity and thereby mass occurrence of these bark beetles.

Phloem and defence traits in relation to tree size and age: Implications for host selection by bark beetles

Tree size often predicts the occurrence of bark beetles that breed in the inner bark (phloem) of trees. A notable example is mountain pine beetle, Dendroctonus ponderosae, which primarily kills large, old trees during outbreaks. The tree mortality pattern is often attributed to increasing phloem thickness with tree size, although tree size-dependent defences may also be important. Age effects may confound interpretations of tree size effects. We examined phloem and anatomical defence traits in single-cohort lodgepole pine, Pinus contorta, stands as a function of tree size and age within and across young mature stands (trees 25–45 years old) and old stands (115–140 years old). Phloem thickness increased linearly with tree size within and across stands, more strongly for trees in young stands that had thicker phloem than same-sized trees in old stands. Phloem nitrogen was greater in young stands and did not vary with tree size. Resin duct investment was generally greater in larger trees within stands, but young trees had more and larger ducts than old trees. These results are consistent with canopy dominance of larger trees within stands that can acquire more carbon for both growth and defence; relationships between tree size and both phloem and defence traits were weaker across stands of different ages. Greater defence in young trees may reflect greater risk and costs of herbivory that might be associated with higher phloem nitrogen in younger stands. Our results suggest that the best phloem resources (quantity and quality) are found in relatively large trees in young stands, which is a poor match for the pattern of attacks by mountain pine beetles that favour large trees in old stands. Lower defences in old stands may also explain the pattern of tree mortality by beetles. Other benefits of large trees merit more attention in understanding the importance of tree size to bark beetles.

Como mudanças climáticas globais podem influenciar na distribuição geográfica do besouro amarelo do eucalipto? Modelagem e predição para o Brasil

Abstract Popularly known as the yellow eucalyptus beetle, Costalimaita ferruginea (Fabricius, 1801) (Coleoptera: Chrysomelidae), in the adult phase it feeds on the leaves of the myrtaceae, leaving them laced, a fact that impairs the productivity of plantations. Therefore, this work aims to model the potential distribution of the beetle in climate change scenarios for Brazil. The biotic data were collected through a review of the literature and entomological collections, totaling 88 georeferenced points of occurrence of the insect in the country. The abiotic data (19 biovariables, precipitation and minimum, average and maximum temperature) in the Wordcllim database, represent the periods: current (1970-2000), middle (2041-2060), and final (2061-2080) of the century, with representation in two projections of climatic anomalies (RCP 4.5 and RCP 8.5). To determine the most important variables for the models, the Jackknife test was performed in the Maxent software, which resulted in five biovariables, namely: annual precipitation (35.2%), temperature seasonality (15.2%), annual temperature variation (13.7%), seasonality of precipitation (8.7%) and an average temperature of the coldest quarter (7.4%). Subsequently, the Openmodeller software was used and five algorithms were tested to determine which model represents the prediction of areas of suitability for the occurrence of the insect. The algorithm that best represented the appropriate areas was the Envelope Score (AUC = 0.808), corroborating the occurrence data collected. The prediction shows that the Pampa biome, in the RCP8.5 scenario for the period between 2061-2080, will become fully suitable for the occurrence of this defoliator beetle, unlike the Amazon, which presents retraction in areas suitable for the occurrence of the beetle for the same period. In this sense, commercial eucalyptus plantations implemented in climatologically suitable areas for the occurrence of this insect must be monitored periodically.

Scarabs in the dark: occurrence of Scarabaeoidea beetles (Insecta: Coleoptera) in Brazilian caves

Scarabeoidea (Insecta: Coleoptera) present more than 2000 species recorded from all over Brazil. They have been scarcely recorded from caves, and truly troglobitic species are yet to be found in the country. In this study, we carried out a review of all existing scarab beetles deposited until 2017 in the Coleção de Invertebrados Subterrâneos de Lavras (ISLA), at the Universidade Federal de Lavras (UFLA) (Minas Gerais, Brazil), one of the most important collections of subterranean invertebrates in South America. Ninety-two individuals belonging to 52 species were recorded, distributed in six families (Cetoniidae, Hybosoridae, Melolonthidae, Passalidae, Scarabaeidae and Trogidae). Scarabaeidae was the most diverse of them, representing more than 50% of the total of species recorded. We found Scarabeoidea beetles in 51 of the ~ 1600 caves examined, distributed in nine Brazilian states: Alagoas, Bahia, Distrito Federal, Espírito Santo, Goiás, Minas Gerais, Pará, Piauí, and Tocantins. Our results provide evidence that Scarabaeoidea beetles are not frequent in Brazilian caves, and their records in this kind of environment are mostly accidental. Exceptions include Trogidae and Aphodiinae species, which may be associated with bat guano. Our study presents the first list of Scarabaeoidea species sampled in Brazilian caves.

Laufkäfer (Coleoptera: Carabidae) auf einer jungen Waldweide: eine Fallstudie aus Südwest- Deutschland

Historical experience shows that wood-pastures provide high habitat diversity and thus also a high degree of species diversity, and as such they have been under discussion for some years as a conservation measure. However, the development of vegetation and various groups of animals on newly grazed wood-pastures is only poorly understood. Comparative approaches, such as the exclosure of certain areas, are required for an evaluation of these developments from a nature conservation perspective. By fencing off a wood-pasture which had been used by heck cattle for six years we were able to analyse the direct effects of grazing on habitat structure and the occurrence of ground beetles. We compared catches from pitfall traps placed in paired 10 x 10 m plots. We recorded a total of 1520 ground beetle individuals from the grazed and the non-grazed plots and found a 52 % greater activity density on the grazed plots, in particular of Carabus nemoralis and the most frequently found species, Nebria brevicollis. Grazing did not have an effect on species richness: it did, however, result in higher light intensity and a higher proportion of grass and had direct effects on the structure of the ground beetle community. Typical colonisers of open vegetation structures or of semi-open woodland, such as Carabus monilis and Carabus arvensis were only found in grazed areas. Further species were hand caught in the grassland and lowland moor areas of the wood-pasture, with a total of 31 ground beetle species now recorded. The increasingly heterogeneous nature of the relatively young wood-pasture clearly promotes species richness. Year-round grazing leads to more open areas of woodland, providing long-term benefits for thermophilous forest species.

Predatory insects in collapsing foci of bark beetles in Sumy region

Introduction
 The outbreaks of the bark beetles Ips acuminatus (Gyllenhal, 1827) and Ips sexdentatus (Boerner, 1767) (Coleoptera: Curculionidae: Scolytinae) have begun to collapse, while the prevalence of Tomicus piniperda (Linnaeus, 1758) and Tomicus minor (Hartig, 1834) is beginning to increase. Given that most predatory beetles attack different species of bark beetles, it is still important to study the occurrence of such predators in forest stands and to rear these entomophages for forest protection. Since predators consume bark beetles at different stages during rearing, it is also advisable to recognize the features of bark beetles spread in collapsing foci to determine the optimal places and time for their collection.
 The aim of the research was to evaluate the occurrence of bark beetles (Coleoptera: Scolytinae) and their predators in collapsing foci depending on certain stand characteristics.
 Materials and Methods
 The study was carried out in collapsing foci of bark beetles in Scots pine (Pinus sylvestris L.) stands in Sumy region. Sample trees of the 5th and 6th categories of health condition were analysed at 30 sample plots in three state forest enterprises of Polissya part of Sumy region and in seven state forest enterprises of the Forest-Steppe part of Sumy region (9 and 21 forestries respectively). Insects were counted on 25 ? 25 cm pallets from mid-May to mid-August 2021. Predatory insects were collected from each pallet to individual Eppendorf tubes, labeled, and later identified in the laboratory.
 Results and Conclusions
 The six predator Coleoptera species were found in the declining stage of outbreak cycle of bark beetles Ips acuminatus (Gyllenhal, 1827) and Ips sexdentatus (Boerner, 1767), namely Aulonium ruficorne (Olivier, 1790) (Colydiidae), Platysoma elongatum (Leach, 1817) (Histeridae), Rhizophagus depressus (Fabricius, 1792) (Monotomidae), Corticeus pini (Panzer, 1799) (Tenebrionidae), Thanasimus formicarius (Linnaeus 1758), and Thanasimus femoralis (Zetterstedt, 1828) (Cleridae). Platysoma elongatum and Aulonium ruficorne had the highest frequency of occurrence in the second decade of May, Thanasimus formicarius in the 3rd decade of May, Corticeus pini in the 1st decade of June, Rhizophagus depressus, Platysoma elongatum, and Aulonium ruficorne in the 3rd decade of June. The fragments of the stem with bark beetles for predators’ rearing have to be collected from the trees of the 5th category of health condition. It is necessary to collect Thanasimus formicarius for rearing in the 3rd decade of May and in the 1st decade of August, and Rhizophagus depressus, Platysoma elongatum, and Aulonium ruficorne – in the 3rd decade of June.

Ecological network for species dependent on ancient broadleaf trees using Osmoderma barnabita as a model species: a new approach

Abstract Organisms that depend on rare and endangered microhabitats, such as old, hollow trees, have a high conservation value. To conserve these species, it is necessary to apply methods that identify habitats suitable for their survival. Until now, a comprehensive method has not been developed for predicting the occurrence of species associated with old, hollow trees. Here, we developed criteria to identify habitats for organisms associated with old, hollow trees, using Osmoderma barnabita as a model species. We used hexagonal tessellation to identify suitable habitats for hermit beetle. Criteria for predicting the occurrence of a hermit beetle were applied in practise, and as result 47.56% of the known hermit beetle localities coincided with the hexagons where the probability of occurrence of the species was the highest. Based on these results, an ecological network was created for species dependency on old, hollow trees, using the hermit beetle as a model species. The proposed approach makes it possible to plan and implement environmental protection measures for species living in territories spanning several countries. In this work, we propose a method to identify species occurrence in core areas and to determine ecological corridors and gaps. This method could tailor conservation planning efforts.

First Record of the Saproxylic Beetle Cossonus parallelepipedus (Coleoptera, Curculionidae) in Bosnia and Herzegovina

Balkan Peninsula is considered to be a hotspot of beetle biodiversity. Registering occurrence of saproxylic beetles is an important first step for expanding the general knowledge about saproxylic beetles as ecologically important insect species. Cossonus parallelepipedus is a European saproxylic species distributed from Iberian Peninsula in the west to Russia in the east, and from the Mediterranean in the south to Fennoscandia in the north. The first, and until now the only find of this species for the Balkan Peninsula is from Croatia. We report the first find of C. parallelepipedus in Bosnia and Herzegovina (BiH). In April 2020, larvae, pupae and imagoes were collected, in the central part of BiH, north of Sarajevo, on Zvijezda Mt. near Vareš from decaying moist wood in the lower part of a tree trunk of European silver fir, Abies alba. We expect that this species has a wider presence, especially in mountain areas in the central part of the country. Due to the similar environment conditions for other two European Cossonus species ( C. cylindrus and C. linearis) their presence is also possible.

Driving factors and their interactions of carabid beetle distribution based on the geographical detector method

The decline of insect diversity has received widespread attention as a serious ecosystem problem worldwide. Accurately learning the driving factors of insect decline is difficult because of the complex multitrophic and environmental interactions involved. The scientific interpretation of the factors driving insect distribution is essential to understanding biological systems and the effects of changed environment. Generally, insect distributions result from the interactions of different factors, therefore, understanding how multi-factor interactions effect of carabid distribution is beneficial. Carabid beetles are indicator species in the steppes of northwestern China. Previous studies have focused on the main driving factors of carabid beetle occurrence separately, ignoring the interactions between drivers. Using the Geographical Detector method, a new method of spatial statistics, the interactive influences of 15 variables on carabid beetle distribution were quantified at three steppes in the Ningxia Hui Autonomous region, of northwestern China. The results showed that carabid beetle distribution in the steppes was primarily driven by annual average precipitation (q=0.55). Among the interactions of factors, precipitation ∩ Altitude (q=0.719) was the strongest, followed by precipitation ∩ plant biomass (q=0.677 ), and precipitation ∩ pH value (q=0.677). The areas with the greatest risk of carabid beetle decline are the desert steppe and northern parts of the meadow steppe. This study shows that the Geographical Detector approach was successful for analyzing the driving forces of carabid beetle distribution. Our study also offers a new method for understanding the interactions between different drivers of other animal distributions more broadly.

The Influence of Fine-Scale Grazing Heterogeneity on Dung Beetle Assemblages: What Trait Analysis Teaches Us.

Livestock grazing puts major anthropogenic pressure on biological communities worldwide. Not all species are expected to be affected in the same way, and the impacts will depend on species' traits. Focusing on traits thus helps identify the mechanisms underlying changes in community composition under grazing pressures. We investigated how fine-scale grazing heterogeneity affects the trait composition and diversity of dung beetle assemblages in Western Europe. We sampled dung beetles in habitat patches differing in terms of grazing intensity within rangelands of two distinct biogeographical areas: a Mediterranean lowland steppe and Western alpine meadows. We measured five morphological traits expected to respond to the local-scale filtering pressure exerted by variations in grazing intensity. Using individual-based data, we assessed responses in terms of single-trait mean values in communities and complementary trait diversity indices. We found strong shifts in trait composition and diversity between the habitat patches. In both study areas, variations in habitat conditions are likely to have filtered the local occurrence and abundance of dung beetles by the mean of traits such as body mass (which have several functional implications), as well as traits linked to underground activity. We hypothesize that fine-scale variation in resource availability (i.e., droppings) and disturbance intensity (i.e., trampling) are key drivers of the observed patterns in species assemblages. Trait richness peaks at moderate grazing intensity in both study areas, suggesting that patches with an intermediated level of available resources and soil disturbance enable individuals with a greater range of autecological requirements to coexist.